Tear resistant matrix confining band and retainer for use therewith

ABSTRACT

A tear-resistant matrix-holding band of uniform thickness and an improved retainer for removably supporting the band in an encircling position on a desired bicuspid or molar tooth in a patient&#39;&#39;s mouth. The retainer is supplied in first and second forms.

tates Patent 1 Inventor: Edward Brenner, 800 W. Ameriga Ave., Fullerton, Calif. 92632 Filed: Feb. 20, 1973 Appl. N0.: 333,989

US. Cl. 32/63 I Int. Cl A616 5/12 Field of Search 32/63 References Cited UNITED STATES PATENTS 2,722,745. 11/1955 Brenner 32/63 [1. 11 3,852,885 warmer Dec. 10, 1974 TEAR RESISTANT MATRIX CONFINING 2,722,746 11/1955 Brenner 32/63 BAND D T N FOR USE 2,918,724 12/1959 Thurman THEREWITH 2,995,822 8/1961 Tofflemire 2/1972 Brenner 32/63 Primary Examiner-Antonio F. Guida Assistant Examinef-l Q. Lever [5 7] ABSTRACT A tear-resistant matrix-holding band of uniform thick- 8 Claims, 14 Drawing Figures PATENIEDUEC 10 974 8,852,885

sum 1 or 2 46 FIG.5

' FIG.6

TEAR RESISTANT MATRIX CONFINING BAND AND RETAINER FOR USE THEREWITH BACKGROUND OF THE INVENTION 1. Field of the Invention Tearresistant matrix band and retainer for use therewith.

2. Description of the Prior Art Matrix-holding bands and retainers for use in removably supporting the same on a molar or bicuspid tooth in a patientsmouth are not new, and prior art devices of this nature are described and claimed in U.S. Pat.- Nos. 2,722,745 and 2,722,746 that issued to the applicant on Nov. 8, 1955.

The device disclosed and claimed in the above identified patents have the operational disadvantages that the retainers are of an unduly complicated structure, the bands must be wedged to tighten the matrix against the gingival portion of the tooth and the matrix-holding hands when subjected to a force to hold the same firm are subject to tearing or breaking. In an effort to overcome these disadvantages of the prior art matrixholding bands, the bands are formed with thickened ends, and although this served to minimize the tearing of the bands, it also drastically increased the cost of producing the same. Furthermore, in order to side slip the band to remove itafter the restoration is completed the thickened ends can not be passed through the tight contact points without mutilating that part ofthe new restoration.

vThe primary object in devising the present invention is to supply a matrix-holding band that is of an extremely simple mechanical structure, is of uniform thickness, and one that can withstand very substantial longitudinal tensioning without breaking. A further object in devising the present invention is to supply a retainer for holding a matrix band in an encircling position on a tooth, which retainer characterized by having an extremely simple mechanical structure, is capable of being easily cleaned after use, as well as less expensive to produce than previously available retainers.

I SUMMARY OF THE INVENTION The matrix holding band is an elongate, rectangular shape and is of uniform thickness. The band is formed from a material such as rolled stainless steel or the like that is not adversely affected by mercury and chemicals present in amalgams, silicates, and acrylics. Each band has a number of longitudinally. spaced openings in the end portions thereof, which openings may be transversely aligned when the band is formed into a loop.

The retainer is suppliedin first and second forms with each form comprising the same combination of elements, but differing in shape on'first ends thereof. The first and second forms permit the band to be placed in a tooth encircling position in predetermined quadrants of a patients mouth as previously described. Both the first and second forms have insignia on the first ends thereof, which insignia when disposed adjacent to the gingival indicate to the dentist that the retainer is correctly positioned in the proper quadrant of the users mouth. 7

The retainer includes an elongate rod that has a number of longitudinally spaced transverse recesses therein that are partially defined by transverse body shoulders that engage a number of edge portions of a matrix confining band when the latter is in a loop defining configuration. The rod has threads formed thereon intermediate the first and second ends thereof, with the threads capable of being removably engaged by a knurled nut. The rod is supported for longitudinal movement in an elongate rigid barrel of non-circular transverse crosssection, which barrel is positioned within the confines of a tubularhousing also of non-circular transverse cross-section. First end portions of the barrel and housing are shaped to define a forwardly and inwardly tapering face on which an insignia is'positioned. The insignias when disposed adjacent the gingivalindicate to the dentist using the retainer that the retainer is disposed in the correct quadrant in the patients mouth. The primary purpose in devising the present invention is to supply an improved retainer band of uniform thickness that is resistant to tearing when a substantial longitudinal force is exerted thereon, as well as an improved retainer of simplified structure for positioning the band in a matrix-holding position on a molar or bicuspid in a patients mouth.

BRIEF DESCRIPTION OF THE DRAWINGS a longitudinally movable rod adapted to removably engage the band;

FIG. 2 is'a fragmentary longitudinal cross-sectional view of the band and retainer taken on the line 2-.2 of FIG. 1;

FIG. 3 is a side elevational view of a portion of the band and retainer taken on line 3-3 of FIG. 2;

FIG. 4 is a side elevational view of a first form of the improved tear resistant band;

FIG. 5 is a side elevational view of a second form of the band;

FIG. 6 is a top view of the band shown in FIG. 4;-

FIG. 7 is a side elevational view of the first form of band shown in FIG. 1 disposed in a tooth encircling loop, and being so held in a tensioned position on a tooth by a retainer, with the retainer having an insignia thereon to indicate that the retainer is disposed in the correct quadrant of a patients mouth;

FIG. 8 is a top plan view of the band and retainer shown in FIG. 7, with the band encircling a tooth in a patients mouth;

FIG. 9 is a side elevational view of the retainer and band, and illustrating the manner by which the band is easily disengaged from the tension applying rod;

FIG. 10 is a transverse cross-sectional view of the retainer taken on the line 10-10 of FIG. 9;

FIG. 11 is a perspective view of the retainer, and taken on the side opposite thereof from that shown in FIG. 1;

FIG. 12 is a side elevational view ofa second form of rod used in applying tension to a looped band, and knurled nut that engages an intermediately threaded portion thereof;

FIG. 13 is a side elevational view of a third form of matrix holding band; and

FIG. 14 is a fragmentary top plan view of a first end portion of the second form of rod and illustrating the manner in which the same removably engages the third form of band when the latter is in a looped position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The retainer A as best seen in FIGS. 1, 2 and 3 and 7-11. inclusive includes an elongate barrel B that has a bore 10 extending longitudinally therethrough. The bore 10 slidably and rotatably supports a first form of rod C that is adapted to removably engage either the first or second form of matrix holding bands D and E. The first and second forms of bands D and E are shown inFIGS. 4 and 5.

Retainer A also includes a tubular cover F that envelopes the major portion of the barrel B. The barrel B and the tubular cover F are of noncircular transverse cross-section and are illustrated in FIG. 11 as each including a longitudinally extending flattened section 12.

- The barrel B is held in a fixed position within the cover and a cantilever member on the secondside thereof.

The cantilever member 20 projects forwardly beyond the barrel B a substantial distance as can best be seen in FIG. 2. Face.l8 has a downwardly and slightly forwardly extending edge 22.

The first form of rod C as can best be seen in FIG. 2 has a longitudinal recess 24 in the first forward end portion 26 thereof, and first and second transverse recesses 28 and 30 situated rearwardly from the recess 24. The first longitudinal recess 24 and the first transverse recess 28 cooperate to define a first portion 32 therebetween on which a first body shoulder 34 is formed. First and second transverse recesses 28 and 30 cooperate to define a transverse rod portion 36 therebetween on which a second body shoulder 38 is defined.

The first end 26 of the rod C includes a guide portion 26a that projects beyond the-balance of the rod. The first form of band D ascan best be seen in FIG. 5 is formed from a rolled sheetof thin material such as stainless steel, with the grain structure of the material defining the sheet extending longitudinally relative to the band D. The first form of band D is defined by two angula'rly disposed elongate sections 40 as shown in FIG. 5 that at their junction define an apex 42. Each section 40 has two longitudinally spaced openings 44 and 46, formed in the free end portion thereof, and these openings capable of being transversely aligned I with-one another when the band D is in the looped configuration as shown in FIGS. 7 and 8, and portions. of the sections in abutting contact with one another.

The first form of rod C as can best be seen in FIG. 1 has intermediate threaded portion 48 that may be engaged by a knurled nut G. The second end of rod C terminates in a cylindrical handle H that is preferably of smaller diameter that the nut G.

When it is desired to place one of the first form of bands D on the first form of rod-C, the band is formed into a loop defining configuration where the sections 40 are at least partially in abutting contact, and the openings 44 and 46 in each section aligned with the openings in the other section. The second openings 46 rod, after the rod has been moved outwardly beyond the barrel B. With the looped band D in engagement with the first rod C as above described, the rod. portion 32 may be caused to pass through the two aligned second openings 46, with the pair of openings 44 engaging the transverse rod portion 36 as shown in FIG. 2. As the looped band D is moved into engagement with the rod portions '32 and 36, portions of the sections 40 forwardly of the openings 46 are positioned in the longitudinal recess 24. The first rod C is 'now moved rearwardly to cause portions of the contacting sections 40 to move within the confines of the slot 16. The looped band D may now be placed in an encircling position on a tooth .I as shown in FIGS. 7 and 8.

The first rod C is moved rearwardly relative to the barrel B and to the extent that the nut G may be placed in engagement with the threads 48. The nutG by rotation in an appropriate direction draws the first form of rod C rearwardly relative to the barrel B, and in so doing tension is applied to the band D that is in an encircling position on the tooth J .Due to the angulation of the section 40 of the first form of band D relative to one another, the loop formed by the band is tapered and this tapered configuration of the band conforms generally to the bell or tapered exterior configuration of the tooth .I when tension is applied to the band. The gingival edge of the bandis secured tight all around the circumference of the tooth at the gum line without the use of wedges. It will be particularly noted that the barrel B on the tapered face 18 thereof has an insignia K formed in the, lower portion thereof, and like insignias are formed on the lower end portions of the band D. The purpose of the insignia K on the tapered face 18 is to be certain that this lower portion is adjacent the gingival in the patients mouth, and the insignia K on the band D is for the purpose of indicating to the dentist using the instrument that the band is correctly positioned in the retainer A in order that the tapered configuration ofthe looped band will be in a direction to conform to the bell or taper of the tooth .I as shown in FIG. 7.

The first and second openings 44 and 46 have transverse edges 44a and 46a that are contacted by the body shoulders 34 and 38 as may best be seen in FIG. 2, and when tension is applied to the band when it is in a looped configuration, the force resulting in the tension is applied through these edges. Due to the increased area of the edges 44a and 46a, in contact with the shoulders 34 and 38, there is no tendency for the band to tear out or break when reasonable tension is applied thereto.

Rearward movement of the first form of rod C relative to barrel B is accomplished by rotating the nut G in an appropriate direction, when the nut is in engagement with the thread 48. After the first form of band D has been placed in an encircling position as shown in FIGS. 7 and 8, the tooth .I about which it extends may have matrix applied thereto, or other dental operations performed thereon in which a material is desired to be held within the confines of the band D. 1

It will be particularly noted that due to the tapered configuration of the face 18 and the manner in which the cantilever member 20 is associated therewith, that the retainer A may be disposed to lie at a slight angle relative to the set of teeth J on which work is being performed as shown in FIG. 8.

The second form of band E shown in FIG. 6 has the same structure as the first band D previously described, other than it is straight. The second form of band B is used in the same manner as the first form and preferably on teeth that do not have a substantially tapered exterior surface. The elements of the second band B common to the first band D are identified by the same numerals, but with a prime being added thereto.

In FIG. 9 it will be seen that a looped band D may be easily disengaged from the rod C by the barrel B being retracted until it contacts handle H and then rotated 90 to remove the band by causing the cantilever extension 20 to move the band out of engagement with the transverse rod portion 36 due to the band D contacting .cantilever member 20 as shown in FIG. 9. With the band D disposed as shown in FIG. 9, the instrument A may be moved away from the tooth J to disengage the guide portion 26a from the opening 46.

A second form of rod L is shown in FIG. 12 that may be used with the retainer A in the same manner as previously described, but with the second form of rod L now requiring the use of a third form M of a resilient band, preferably formed from rolled stainless steel or the like. The second form of rod L has an intermediately threaded portion 48 and a cylindrical handle H on one end thereof. The threads 48 may be engaged by a knurled nut G in the same manner as the threads 48 are engaged by the nut G in the first form of the device.

The third form M of the bandlike the first form D is defined by two angularly positioned elongate sections 50. The second form of rod L as shown in FIG. 12 on a first end 52 thereof defines a longitudinally extending slot 54 that is partially defined by a guide member 56 that extends forwardly beyond the balance of the rod. First. second and third transverse recesses 58, 60 and 62 are formed in the rod rearwardly of the slot 54 and are partially defined by body shoulders 58a, 60a and 620. Each of the sections 50 of the band M have first, second and third longitudinally spaced openings 64, 66 and 68 formed therein, and the openings being partially defined by edges 64a, 66a and 68a.

When the band M is placed in alooped configuration with portions of the section 50 in abutting contact, the opening 64, 66'and 68 therein may be transversely aligned with one another. After the openings 64, 66 and 68 have been so aligned, the bands may-be removably mounted on the second form 'L of the rods, as shown in FIG. 14, with the edges 64a, 66a, and 68a being in contact with the body shoulders 58a, 60a, and 62a. When tension is applied to the looped band M that is so disposed on the rod L, the force creating the tension is transmitted to the band through the edges 64a, 66a and 68a, andasa result there is no tendency for the band to tear at the openings even when a very substantial force is exerted on the band to force it into encircling contact with the tooth. The use of the second form of rod Land third form of band M permits the band to be placed in greater pressure contact with the exterior surface of a tooth .I than is possible with the form of bands D and E previously described. The secnd form of rod L and the third form of band M are used in the retainer A in the same manner as previously described in connection with the first form of rod C and the first and second bands D and-E, and this information need not be repeated.

The retainer A is not only supplied in the first form shown in FIG. 1, but in a second form (not shown) that includes the same combination of elements as the first form, but with the position of the fact 18 reversed to permit the retainer to be used on teeth in quadrants of the patients mouth for which the first form is not suited. I

It will be particularly noted that the cover F and the slot 16 cooperate to define a longitudinally extending confined space in which the abutting sections 40 of the band D are disposed when the band is in the looped position illustrated in FIG. 1. Due to the sections so engaging the confined space, the band is held in a nonrotatable position relative to the retainer A. The interior surface of the barrel B in the portion thereof that defines slot 16 has a longitudinal groove 21 therein that is axially aligned with the bore 10, and the groove continuing forwardly on the interior face of the cantilever member 20 as shown in FIG. 1. The groove 21 is slidably and rotatably engaged by rod C, and the rod as a result is at all times maintained in fixed longitudinal alignment with the retainer A. 1

- The use and operation of the retainer A has been previously explained in detail and need notbe repeated.

I claim:

1. In combination with an elongate tear-resistant, r'esilient dental matrix-confining band, which when formed into a loop, defines two sections having portionsthereof in abutting contact, in whichportions a plurality of longitudinally spaced, transversely aligned openings are formed that are partially defined by first forwardly disposed transverseedges of said band, a retainer for disposing said looped band in a tensioned encircling position on a tooth in a patients mouth, which retainer includes:

a. a rigid elongate barrel of non-circular transverse cross section that has a first forward end portion in which a longitudinal slot is formed that is in communication with a longitudinal bore that extends to a second end of said barrel, said first end portion being defined by a forwardly extending cantilever member on a first side of said slot and an inwardly and forwardly tapered face on a second side of said slot, with said cantilever member being on the side thereof adjacent said tapered face having a longitudinally extending guide groove formed therein that is in alignment with and communicates with said bore;

b. a tubular cover of non-circular transverse cross section that slidably and frictionally engages the exterior of said barrel and envelops at least that portion thereof in which said slot is formed, with said cover on a first forward end thereof terminating at substantially the rear end of said cantilever member, and said cover cooperatively providing a longitudinal confined space open at the forward end thereof;

c. an elongate rod having a first end and a second end and threads formed thereon intermediate therebetween, which first end has a first longitudinal recess formed therein and a plurality of longitudinally spaced transverse recesses'rearwardly therefrom, with each of said transverse recesses being partially defined by a transverse body shoulder, and with said longitudinal recess and said transverse recessaid openings when said abutting sections extend rearwardly in said confined space in contact with said rod, with said rod when moved rearwardly relative to said barrel and cover applying a force through said body shoulders to said first edges to tension said band in a looped configuration about a tooth, and said band due to the plurality of the areas of said first edges through which said force is exerted, not tearing as a result of said force so applied;

d. a nut slidably and rotatably mounted on said rod rearwardly of said threaded portion, with said nut when rotated in engagement with said threaded portion and in abutting contact with said second end of said barrel moving said rod rearwardly relative thereto; and

e. a handle on said second end of said rod for moving said rod forward relative to said longitudinal slot in the elongate barrel when said nut is not in engagement with said threaded portion, to the extent said abutting portions of said band sections are moved out of said confined space in which they are held in a non-rotatable position relative to said barrel and are at least partially disengaged from said rod when said barrel is rotated 90 relative to said rod to move said abutting band sections into pressure contact with said cantilever member of said barrel, with said rod when said rotation takes place remaining aligned with said bore due to slidably and rotatably engaging groove in said cantilever member.

2. The combination as defined in claim 1 in which said band is formed from a sheet material of uniform thickness and with said sections angularly disposed and meeting at an apex, with said band when formed into a loop tapering transversely in the same direction as the exterior surface of the tooth on which said band is disposed. r g

3. The combination as defined in claim 2 which further includes: 1

f. first insignia means on said retainer for visually indicating that saidretainer is being used on a tooth in the correct quadrant of a patients mouth.

4. The combination as defined in claim 3 which further includes:

g. second insignia means on said band for visually indicating said band is correctly positioned in said retainerand the taper thereof will conform to the taper of the exterior surface of a patients tooth when said band is tensioned in an encircling position about the latter by rotation of said nut.

5. The combination as defined in claim 1 in which said band is of elongate shape and formed from a resilient material of uniform thickness, which band includes two elongate sections that have portions thereof in abutting contact when said band is in a looped configuration, with said portions having a plurality of transversely aligned openings formed therein, each of which openings is partially defined by a transverse edge through which force is applied to tension said band as a loop about a patients tooth, with the material defining said band resisting tearing when tension is applied thereto due to the plurality of areasvof said edges through which said force is applied to said band.

6. The combination as defined in claim 1 wherein said sections are angularly disposed relative to one another and said band when formed into a loop tapers transversely in a direction to conform to'the tapered exterior surface of said tooth.

7. Thecombination as defined in claim 1 wherein the material defining said band is rolled metal having a grain structure, said metal being of uniform thickness and said grain structure extending longitudinally 'rela tive to said band to increase the strength of said band when tension is applied thereto.

8. A band as defined in claim 1 that further includes insignia means thereon to visually indicate the edge thereof that is to be disposed adjacent the gingival. 

1. In combination with an elongate tear-resistant, resilient dental matrix-confining band, which when formed into a loop, defines two sections having portions thereof in abutting contact, in which portions a plurality of longitudinally spaced, transversely aligned openings are formed that are partially defined by first forwardly disposed transverse edges of said band, a retainer for disposing said looped band in a tensioned encircling position on a tooth in a patient''s mouth, which retainer includes: a. a rigid elongate barrel of non-circular transverse cross section that has a first forward end portion in which a longitudinal slot is formed that is in communication with a longitudinal bore that extends to a second end of said barrel, said first end portion being defined by a forwardly extending cantilever member on a first side of said slot and an inwardly and forwardly tapered face on a seconD side of said slot, with said cantilever member being on the side thereof adjacent said tapered face having a longitudinally extending guide groove formed therein that is in alignment with and communicates with said bore; b. a tubular cover of non-circular transverse cross section that slidably and frictionally engages the exterior of said barrel and envelops at least that portion thereof in which said slot is formed, with said cover on a first forward end thereof terminating at substantially the rear end of said cantilever member, and said cover cooperatively providing a longitudinal confined space open at the forward end thereof; c. an elongate rod having a first end and a second end and threads formed thereon intermediate therebetween, which first end has a first longitudinal recess formed therein and a plurality of longitudinally spaced transverse recesses rearwardly therefrom, with each of said transverse recesses being partially defined by a transverse body shoulder, and with said longitudinal recess and said transverse recesses having rod portions therebetween that engage said openings when said abutting sections extend rearwardly in said confined space in contact with said rod, with said rod when moved rearwardly relative to said barrel and cover applying a force through said body shoulders to said first edges to tension said band in a looped configuration about a tooth, and said band due to the plurality of the areas of said first edges through which said force is exerted, not tearing as a result of said force so applied; d. a nut slidably and rotatably mounted on said rod rearwardly of said threaded portion, with said nut when rotated in engagement with said threaded portion and in abutting contact with said second end of said barrel moving said rod rearwardly relative thereto; and e. a handle on said second end of said rod for moving said rod forward relative to said longitudinal slot in the elongate barrel when said nut is not in engagement with said threaded portion, to the extent said abutting portions of said band sections are moved out of said confined space in which they are held in a non-rotatable position relative to said barrel and are at least partially disengaged from said rod when said barrel is rotated 90* relative to said rod to move said abutting band sections into pressure contact with said cantilever member of said barrel, with said rod when said rotation takes place remaining aligned with said bore due to slidably and rotatably engaging groove in said cantilever member.
 2. The combination as defined in claim 1 in which said band is formed from a sheet material of uniform thickness and with said sections angularly disposed and meeting at an apex, with said band when formed into a loop tapering transversely in the same direction as the exterior surface of the tooth on which said band is disposed.
 3. The combination as defined in claim 2 which further includes: f. first insignia means on said retainer for visually indicating that said retainer is being used on a tooth in the correct quadrant of a patient''s mouth.
 4. The combination as defined in claim 3 which further includes: g. second insignia means on said band for visually indicating said band is correctly positioned in said retainer and the taper thereof will conform to the taper of the exterior surface of a patient''s tooth when said band is tensioned in an encircling position about the latter by rotation of said nut.
 5. The combination as defined in claim 1 in which said band is of elongate shape and formed from a resilient material of uniform thickness, which band includes two elongate sections that have portions thereof in abutting contact when said band is in a looped configuration, with said portions having a plurality of transversely aligned openings formed therein, each of which openings is partially defined by a transverse edge through which force is applied to tension said band as a loop about a patient''s tooth, with thE material defining said band resisting tearing when tension is applied thereto due to the plurality of areas of said edges through which said force is applied to said band.
 6. The combination as defined in claim 1 wherein said sections are angularly disposed relative to one another and said band when formed into a loop tapers transversely in a direction to conform to the tapered exterior surface of said tooth.
 7. The combination as defined in claim 1 wherein the material defining said band is rolled metal having a grain structure, said metal being of uniform thickness and said grain structure extending longitudinally relative to said band to increase the strength of said band when tension is applied thereto.
 8. A band as defined in claim 1 that further includes insignia means thereon to visually indicate the edge thereof that is to be disposed adjacent the gingival. 